Core oil



Patented May 23, 1933 UNITED STATES PAT NT en GEORGE F. KENNEDY, OF NEWBURYPOBT, MASSACHUSEIEPS, ASSIGNOB TO HERCULES POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION 01' DELAWARE CORE OIL IbIoDrawiugs Original application flled lugust 10, 1928, Serial No. 298,867. Divided and this application filed December 4, 1931. Serial No. 579,119.

My invention relates to a method for preventing the crystallization of abietic acid and rosin, as such, or where compounded with other materials, as for example, in core oils,

printing inks, etc." I

' its is well known abietic acid and rosin, both gum rosin and wood rosin, have a tendency to crystallize and will crystallize in time, as when they are stored or when they are compounded with other materials, as for example, in core 0115. The presence of crystals 1n abletlc acid or in rosin is a serious oh- 7 jection to their use, since when crystallized discovered that crystallization of abietic acidand rosin may beprevented or desirably retarded by subjecting the abietic acid or rosin to partial oxidaltion, which may be accomplished, fofexample, by blowing with air or subjecting them to treatment with an oxidizing agent. When the partial oxidationof the abiet e acid or rosin is effected by blowing with air, the substance under treatment may, for example, be in solution in a suitable solvent such,-for example, as gasoline, and the air blown through the solution, or as dis solved, for example, in linseed oil for the production of a core oil. Where air is blown through a solution of abietic acid or rosin,

the solvent carried oil by the air in the form of vapor is condensed and the partially oxidized abietic acid or recovered irom the solution by evaporation oil of the solvent. The abietic acid or romn may be blown with' air while in a molten condition, and

preferably maintained at a temperature of,

from about 100 C. to about 250 (1., for a period of time depending upon'the temperature, volume of air and degree of contact with the air, and degree of retardation of tendency to crystallize desired. For example, abietic acid or rosin, after air blowing for about eight hours, while maintained at a tempera ture of about 200 C., will be found to have a greatly reduced tendency to crystallize, as compared with untreated abietic acid or rosin. Air blowing for a shorter period than eight hours, say four hours, or at a temperature lower than 200 (3., will give an improved abieticacid or rosin and air blowing for a longer period than eight hours will still further decrease the tendency of theabietic acid or rosin to crystallize. The air blowing fect of reducing the acid number thereof.

. By way of illustration of the treatment, for example, of rosin for its partial oxidation, the rosin may be treated in solution, for ex- ,ample, in an ingredient of core oil,.as linseed oil. For example, in the production of a 'core oil 40 parts of rosin dissolved in 30 parts 7 12 hours at a temperature of say C. and

of linseed oil are blown with air for say the necessary amount of kerosene oil then iidded. Abietic acid may be treated similar- The partial oxidation of abietic acid or rosin may, as has been indicated, be efiected by treatment with, forexample, oxygen, air, or other gas containing oxygen, or with small amounts of ozone, or by treatment with a reagent which liberates oxygen such as potassium permanganate, sodium bichromate, etc.

As illustrative of the retardation of the tendency of, for example, resin to crystallize, a core oil, comprising 30 arts linseed oil, 30 parts of kerosene oil antf-iO parts of rosin, which hasbeen previously blown with air for about eight hours, while maintained at a temperature of 200 C., and the acid number of which will be found to have been reduced from about to about 147, will not crystallize after standing at room temperature for five weeks, where a similar core oil c'ontaining untreated rosin will begin to crystallize in' six days. A core oil as above, containing 100 of abietic acid or rosin will also have theefrosin which has been air blown for a periodof about four hours, will resist crystallization for about twelve days.

It will be understood that my invention contemplates fundamentally preventing or retardation of the tendency of abietic acid and rosin to crystallize by partial oxidation a of the abietic acid or rosin however effected and that my invention is applicable to abietic acid and to both gum and woodrosin, which, as well lmown, are impure forms of abietic aci j I have not herein claimed the method for preventing the crystallization of abietic acid 1 and rosin described, since such forms the subject matter of an application for United States Letters Patent filed by me Serial No. 298,867, filed August 10, 1928, and of which this application is a division. What I claim and desire to protect by Letters Patent is:

1. A core oil substantially resistant tocrystallization, which includes abietic acid. which 7 has been subjected to treatment to effect its partial oxidation and a petroleum oil as ingredients. V i f 2. A core oil substantially resistant to crystallization, which includes rosin, which has been subjected to treatment to effect its 80 partial oxidation and a petroleum oil as ingredients.

3. A core oil substantially resistant to crystallization, which includes as ingredients linseed oil, a petroleum distillate and abietic 35. acid which has been subjected to treatment to efiect its partial oxidation.

' 4. A core oil substantially resistant to crystallization, which includes as ingredients linseed oil, a petroleum distillate and rosin 40 which has been subjected totreatment to effect its partial oxidation. j

In testimony of which invention, I have hereunto set my hand, at Newburyport, Mass, em. on this 24th day of November, 1931. v .GEORGEL F. KENNEDY. ,4 v/ 7/ so 3 j 

